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Subject: Re: 0x88 vs mailbox

Author: Volker Böhm

Date: 15:06:54 09/16/04

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Hi Stuard,

  if (board[H8+OFFSET] == OFFBOARD)    <== mailbox

vs.

  if (((H8+OFFSET) & 0x88)))    <== 0x88 method

You can´t say anything about time concerning these two compares. What do you
check where?

Example:
If you have a piece list you never have to check if the starting position is in
board.

Example: Move a white Rook on place to right:

if (((Cur_Pos + Right) & 0x88) || (board[Cur_Pos + Right] & white))
// Expensive

// Check for OFFBOARD or white:
// I Have a bit for "white" one for "black" and one for "offboard"
if (board[Cur_Pos + Right] & (offboard | white))
// Less expensive


Thus 0x88 is not a speed improvement here.




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